Average salaries went up by 5.5 per cent from $1,711 in 2006 to $1.805 last year, according to an annual employment survey jointly conducted by the five polytechnics: Nanyang, Ngee Ann, Republic, Singapore and Temasek, between October and December last year.

The survey polled 11,000 respondents.

Ironically, among the highest earners were students from one of the least popular courses - engineering. Mechanical and manufacturing engineering graduates had a gross monthly salary of $1,923, while electrical and electronic engineering graduates earned $1,895.

But topping the list of high earners are maritime graduates, who take home an average of $1,981 a month.

Mr Tan Kim Pong, Ngee Ann Polytechnic's director of its Marine and Offshore Technology Centre of Innovation, said the massive demand and lack of supply in the maritime industry has brought the pay packets up.

'There aren't enough workers at every level. The shipyards scramble for every batch of students that comes out,' he said on Monday.

To boost supply to the industry, the polytechnic has increased its diploma intake from 60 to 80 students.

It has also tied up with Singapore Polytechnic and the Newcastle University to offer a degree in naval architecture come September.

Apart from higher salaries, more students also found a job last year.

About 75.3 per cent of those who were working or looking for a job, found full-time jobs, up from 72.1 per cent in 2006.

Of these, 87.7 per cent are working in the private sector and 12.3 per cent are in the public sector.